Effects of acidification in multiple stable isotope analyses

Abstract

The effect of in situ acidification on the stable isotope ratios of carbon and nitrogen was tested in several invertebrates living in an eelgrass system. Dried and ground samples of individuals were weighted in silver cups and treated in situ with 10% HCl. Control samples were measured without acidification. This treatment to remove inorganic carbon significantly decreased the δ13C values. The δ15N values were not affected by this method of acidification. In contrast to the acid-washing method the tested procedure seems suitable to remove inorganic carbon in small invertebrate species.